/*
* Copyright (c) 2014 Qualcomm Atheros, Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "ath9k.h"
/* Set/change channels. If the channel is really being changed, it's done
* by reseting the chip. To accomplish this we must first cleanup any pending
* DMA, then restart stuff.
*/
static int ath_set_channel(struct ath_softc *sc)
{
struct ath_hw *ah = sc->sc_ah;
struct ath_common *common = ath9k_hw_common(ah);
struct ieee80211_hw *hw = sc->hw;
struct ath9k_channel *hchan;
struct cfg80211_chan_def *chandef = &sc->cur_chan->chandef;
struct ieee80211_channel *chan = chandef->chan;
int pos = chan->hw_value;
int old_pos = -1;
int r;
if (test_bit(ATH_OP_INVALID, &common->op_flags))
return -EIO;
if (ah->curchan)
old_pos = ah->curchan - &ah->channels[0];
ath_dbg(common, CONFIG, "Set channel: %d MHz width: %d\n",
chan->center_freq, chandef->width);
/* update survey stats for the old channel before switching */
spin_lock_bh(&common->cc_lock);
ath_update_survey_stats(sc);
spin_unlock_bh(&common->cc_lock);
ath9k_cmn_get_channel(hw, ah, chandef);
/* If the operating channel changes, change the survey in-use flags
* along with it.
* Reset the survey data for the new channel, unless we're switching
* back to the operating channel from an off-channel operation.
*/
if (!sc->cur_chan->offchannel && sc->cur_survey != &sc->survey[pos]) {
if (sc->cur_survey)
sc->cur_survey->filled &= ~SURVEY_INFO_IN_USE;
sc->cur_survey = &sc->survey[pos];
memset(sc->cur_survey, 0, sizeof(struct survey_info));
sc->cur_survey->filled |= SURVEY_INFO_IN_USE;
} else if (!(sc->survey[pos].filled & SURVEY_INFO_IN_USE)) {
memset(&sc->survey[pos], 0, sizeof(struct survey_info));
}
hchan = &sc->sc_ah->channels[pos];
r = ath_reset_internal(sc, hchan);
if (r)
return r;
/* The most recent snapshot of channel->noisefloor for the old
* channel is only available after the hardware reset. Copy it to
* the survey stats now.
*/
if (old_pos >= 0)
ath_update_survey_nf(sc, old_pos);
/* Enable radar pulse detection if on a DFS channel. Spectral
* scanning and radar detection can not be used concurrently.
*/
if (hw->conf.radar_enabled) {
u32 rxfilter;
/* set HW specific DFS configuration */
ath9k_hw_set_radar_params(ah);
rxfilter = ath9k_hw_getrxfilter(ah);
rxfilter |= ATH9K_RX_FILTER_PHYRADAR |
ATH9K_RX_FILTER_PHYERR;
ath9k_hw_setrxfilter(ah, rxfilter);
ath_dbg(common, DFS, "DFS enabled at freq %d\n",
chan->center_freq);
} else {
/* perform spectral scan if requested. */
if (test_bit(ATH_OP_SCANNING, &common->op_flags) &&
sc->spectral_mode == SPECTRAL_CHANSCAN)
ath9k_spectral_scan_trigger(hw);
}
return 0;
}
static bool
ath_chanctx_send_vif_ps_frame(struct ath_softc *sc, struct ath_vif *avp,
bool powersave)
{
struct ieee80211_vif *vif = avp->vif;
struct ieee80211_sta *sta = NULL;
struct ieee80211_hdr_3addr *nullfunc;
struct ath_tx_control txctl;
struct sk_buff *skb;
int band = sc->cur_chan->chandef.chan->band;
switch (vif->type) {
case NL80211_IFTYPE_STATION:
if (!vif->bss_conf.assoc)
return false;
skb = ieee80211_nullfunc_get(sc->hw, vif);
if (!skb)
return false;
nullfunc = (struct ieee80211_hdr_3addr *) skb->data;
if (powersave)
nullfunc->frame_control |=
cpu_to_le16(IEEE80211_FCTL_PM);
skb_set_queue_mapping(skb, IEEE80211_AC_VO);
if (!ieee80211_tx_prepare_skb(sc->hw, vif, skb, band, &sta)) {
dev_kfree_skb_any(skb);
return false;
}
break;
default:
return false;
}
memset(&txctl, 0, sizeof(txctl));
txctl.txq = sc->tx.txq_map[IEEE80211_AC_VO];
txctl.sta = sta;
txctl.force_channel = true;
if (ath_tx_start(sc->hw, skb, &txctl)) {
ieee80211_free_txskb(sc->hw, skb);
return false;
}
return true;
}
void ath_chanctx_check_active(struct ath_softc *sc, struct ath_chanctx *ctx)
{
struct ath_common *common = ath9k_hw_common(sc->sc_ah);
struct ath_vif *avp;
bool active = false;
u8 n_active = 0;
if (!ctx)
return;
list_for_each_entry(avp, &ctx->vifs, list) {
struct ieee80211_vif *vif = avp->vif;
switch (vif->type) {
case NL80211_IFTYPE_P2P_CLIENT:
case NL80211_IFTYPE_STATION:
if (vif->bss_conf.assoc)
active = true;
break;
default:
active = true;
break;
}
}
ctx->active = active;
ath_for_each_chanctx(sc, ctx) {
if (!ctx->assigned || list_empty(&ctx->vifs))
continue;
n_active++;
}
if (n_active <= 1) {
clear_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags);
return;
}
if (test_and_set_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags))
return;
ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL);
}
static bool
ath_chanctx_send_ps_frame(struct ath_softc *sc, bool powersave)
{
struct ath_vif *avp;
bool sent = false;
rcu_read_lock();
list_for_each_entry(avp, &sc->cur_chan->vifs, list) {
if (ath_chanctx_send_vif_ps_frame(sc, avp, powersave))
sent = true;
}
rcu_read_unlock();
return sent;
}
static bool ath_chanctx_defer_switch(struct ath_softc *sc)
{
if (sc->cur_chan == &sc->offchannel.chan)
return false;
switch (sc->sched.state) {
case ATH_CHANCTX_STATE_SWITCH:
return false;
case ATH_CHANCTX_STATE_IDLE:
if (!sc->cur_chan->switch_after_beacon)
return false;
sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
break;
default:
break;
}
return true;
}
static void ath_chanctx_set_next(struct ath_softc *sc, bool force)
{
struct timespec ts;
bool measure_time = false;
bool send_ps = false;
spin_lock_bh(&sc->chan_lock);
if (!sc->next_chan) {
spin_unlock_bh(&sc->chan_lock);
return;
}
if (!force && ath_chanctx_defer_switch(sc)) {
spin_unlock_bh(&sc->chan_lock);
return;
}
if (sc->cur_chan != sc->next_chan) {
sc->cur_chan->stopped = true;
spin_unlock_bh(&sc->chan_lock);
if (sc->next_chan == &sc->offchannel.chan) {
getrawmonotonic(&ts);
measure_time = true;
}
__ath9k_flush(sc->hw, ~0, true);
if (ath_chanctx_send_ps_frame(sc, true))
__ath9k_flush(sc->hw, BIT(IEEE80211_AC_VO), false);
send_ps = true;
spin_lock_bh(&sc->chan_lock);
if (sc->cur_chan != &sc->offchannel.chan) {
getrawmonotonic(&sc->cur_chan->tsf_ts);
sc->cur_chan->tsf_val = ath9k_hw_gettsf64(sc->sc_ah);
}
}
sc->cur_chan = sc->next_chan;
sc->cur_chan->stopped = false;
sc->next_chan = NULL;
sc->sched.offchannel_duration = 0;
if (sc->sched.state != ATH_CHANCTX_STATE_FORCE_ACTIVE)
sc->sched.state = ATH_CHANCTX_STATE_IDLE;
spin_unlock_bh(&sc->chan_lock);
if (sc->sc_ah->chip_fullsleep ||
memcmp(&sc->cur_chandef, &sc->cur_chan->chandef,
sizeof(sc->cur_chandef))) {
ath_set_channel(sc);
if (measure_time)
sc->sched.channel_switch_time =
ath9k_hw_get_tsf_offset(&ts, NULL);
}
if (send_ps)
ath_chanctx_send_ps_frame(sc, false);
ath_offchannel_channel_change(sc);
ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_SWITCH);
}
void ath_chanctx_work(struct work_struct *work)
{
struct ath_softc *sc = container_of(work, struct ath_softc,
chanctx_work);
mutex_lock(&sc->mutex);
ath_chanctx_set_next(sc, false);
mutex_unlock(&sc->mutex);
}
void ath_chanctx_init(struct ath_softc *sc)
{
struct ath_chanctx *ctx;
struct ath_common *common = ath9k_hw_common(sc->sc_ah);
struct ieee80211_supported_band *sband;
struct ieee80211_channel *chan;
int i, j;
sband = &common->sbands[IEEE80211_BAND_2GHZ];
if (!sband->n_channels)
sband = &common->sbands[IEEE80211_BAND_5GHZ];
chan = &sband->channels[0];
for (i = 0; i < ATH9K_NUM_CHANCTX; i++) {
ctx = &sc->chanctx[i];
cfg80211_chandef_create(&ctx->chandef, chan, NL80211_CHAN_HT20);
INIT_LIST_HEAD(&ctx->vifs);
ctx->txpower = ATH_TXPOWER_MAX;
for (j = 0; j < ARRAY_SIZE(ctx->acq); j++)
INIT_LIST_HEAD(&ctx->acq[j]);
}
ctx = &sc->offchannel.chan;
cfg80211_chandef_create(&ctx->chandef, chan, NL80211_CHAN_HT20);
INIT_LIST_HEAD(&ctx->vifs);
ctx->txpower = ATH_TXPOWER_MAX;
for (j = 0; j < ARRAY_SIZE(ctx->acq); j++)
INIT_LIST_HEAD(&ctx->acq[j]);
sc->offchannel.chan.offchannel = true;
}
void ath9k_chanctx_force_active(struct ieee80211_hw *hw,
struct ieee80211_vif *vif)
{
struct ath_softc *sc = hw->priv;
struct ath_common *common = ath9k_hw_common(sc->sc_ah);
struct ath_vif *avp = (struct ath_vif *) vif->drv_priv;
bool changed = false;
if (!test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags))
return;
if (!avp->chanctx)
return;
mutex_lock(&sc->mutex);
spin_lock_bh(&sc->chan_lock);
if (sc->next_chan || (sc->cur_chan != avp->chanctx)) {
sc->next_chan = avp->chanctx;
changed = true;
}
sc->sched.state = ATH_CHANCTX_STATE_FORCE_ACTIVE;
spin_unlock_bh(&sc->chan_lock);
if (changed)
ath_chanctx_set_next(sc, true);
mutex_unlock(&sc->mutex);
}
void ath_chanctx_switch(struct ath_softc *sc, struct ath_chanctx *ctx,
struct cfg80211_chan_def *chandef)
{
struct ath_common *common = ath9k_hw_common(sc->sc_ah);
spin_lock_bh(&sc->chan_lock);
if (test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) &&
(sc->cur_chan != ctx) && (ctx == &sc->offchannel.chan)) {
sc->sched.offchannel_pending = true;
spin_unlock_bh(&sc->chan_lock);
return;
}
sc->next_chan = ctx;
if (chandef)
ctx->chandef = *chandef;
if (sc->next_chan == &sc->offchannel.chan) {
sc->sched.offchannel_duration =
TU_TO_USEC(sc->offchannel.duration) +
sc->sched.channel_switch_time;
}
spin_unlock_bh(&sc->chan_lock);
ieee80211_queue_work(sc->hw, &sc->chanctx_work);
}
void ath_chanctx_set_channel(struct ath_softc *sc, struct ath_chanctx *ctx,
struct cfg80211_chan_def *chandef)
{
bool cur_chan;
spin_lock_bh(&sc->chan_lock);
if (chandef)
memcpy(&ctx->chandef, chandef, sizeof(*chandef));
cur_chan = sc->cur_chan == ctx;
spin_unlock_bh(&sc->chan_lock);
if (!cur_chan)
return;
ath_set_channel(sc);
}
struct ath_chanctx *ath_chanctx_get_oper_chan(struct ath_softc *sc, bool active)
{
struct ath_chanctx *ctx;
ath_for_each_chanctx(sc, ctx) {
if (!ctx->assigned || list_empty(&ctx->vifs))
continue;
if (active && !ctx->active)
continue;
if (ctx->switch_after_beacon)
return ctx;
}
return &sc->chanctx[0];
}
void ath_chanctx_offchan_switch(struct ath_softc *sc,
struct ieee80211_channel *chan)
{
struct cfg80211_chan_def chandef;
cfg80211_chandef_create(&chandef, chan, NL80211_CHAN_NO_HT);
ath_chanctx_switch(sc, &sc->offchannel.chan, &chandef);
}
static struct ath_chanctx *
ath_chanctx_get_next(struct ath_softc *sc, struct ath_chanctx *ctx)
{
int idx = ctx - &sc->chanctx[0];
return &sc->chanctx[!idx];
}
static void ath_chanctx_adjust_tbtt_delta(struct ath_softc *sc)
{
struct ath_chanctx *prev, *cur;
struct timespec ts;
u32 cur_tsf, prev_tsf, beacon_int;
s32 offset;
beacon_int = TU_TO_USEC(sc->cur_chan->beacon.beacon_interval);
cur = sc->cur_chan;
prev = ath_chanctx_get_next(sc, cur);
getrawmonotonic(&ts);
cur_tsf = (u32) cur->tsf_val +
ath9k_hw_get_tsf_offset(&cur->tsf_ts, &ts);
prev_tsf = prev->last_beacon - (u32) prev->tsf_val + cur_tsf;
prev_tsf -= ath9k_hw_get_tsf_offset(&prev->tsf_ts, &ts);
/* Adjust the TSF time of the AP chanctx to keep its beacons
* at half beacon interval offset relative to the STA chanctx.
*/
offset = cur_tsf - prev_tsf;
/* Ignore stale data or spurious timestamps */
if (offset < 0 || offset > 3 * beacon_int)
return;
offset = beacon_int / 2 - (offset % beacon_int);
prev->tsf_val += offset;
}
void ath_chanctx_timer(unsigned long data)
{
struct ath_softc *sc = (struct ath_softc *) data;
ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_TSF_TIMER);
}
/* Configure the TSF based hardware timer for a channel switch.
* Also set up backup software timer, in case the gen timer fails.
* This could be caused by a hardware reset.
*/
static void ath_chanctx_setup_timer(struct ath_softc *sc, u32 tsf_time)
{
struct ath_hw *ah = sc->sc_ah;
ath9k_hw_gen_timer_start(ah, sc->p2p_ps_timer, tsf_time, 1000000);
tsf_time -= ath9k_hw_gettsf32(ah);
tsf_time = msecs_to_jiffies(tsf_time / 1000) + 1;
mod_timer(&sc->sched.timer, tsf_time);
}
void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif,
enum ath_chanctx_event ev)
{
struct ath_hw *ah = sc->sc_ah;
struct ath_common *common = ath9k_hw_common(ah);
struct ath_beacon_config *cur_conf;
struct ath_vif *avp = NULL;
struct ath_chanctx *ctx;
u32 tsf_time;
u32 beacon_int;
bool noa_changed = false;
if (vif)
avp = (struct ath_vif *) vif->drv_priv;
spin_lock_bh(&sc->chan_lock);
switch (ev) {
case ATH_CHANCTX_EVENT_BEACON_PREPARE:
if (avp->offchannel_duration)
avp->offchannel_duration = 0;
if (avp->chanctx != sc->cur_chan)
break;
if (sc->sched.offchannel_pending) {
sc->sched.offchannel_pending = false;
sc->next_chan = &sc->offchannel.chan;
sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
}
ctx = ath_chanctx_get_next(sc, sc->cur_chan);
if (ctx->active && sc->sched.state == ATH_CHANCTX_STATE_IDLE) {
sc->next_chan = ctx;
sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
}
/* if the timer missed its window, use the next interval */
if (sc->sched.state == ATH_CHANCTX_STATE_WAIT_FOR_TIMER)
sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON)
break;
sc->sched.beacon_pending = true;
sc->sched.next_tbtt = REG_READ(ah, AR_NEXT_TBTT_TIMER);
cur_conf = &sc->cur_chan->beacon;
beacon_int = TU_TO_USEC(cur_conf->beacon_interval);
/* defer channel switch by a quarter beacon interval */
tsf_time = sc->sched.next_tbtt + beacon_int / 4;
sc->sched.switch_start_time = tsf_time;
sc->cur_chan->last_beacon = sc->sched.next_tbtt;
/* Prevent wrap-around issues */
if (avp->periodic_noa_duration &&
tsf_time - avp->periodic_noa_start > BIT(30))
avp->periodic_noa_duration = 0;
if (ctx->active && !avp->periodic_noa_duration) {
avp->periodic_noa_start = tsf_time;
avp->periodic_noa_duration =
TU_TO_USEC(cur_conf->beacon_interval) / 2 -
sc->sched.channel_switch_time;
noa_changed = true;
} else if (!ctx->active && avp->periodic_noa_duration) {
avp->periodic_noa_duration = 0;
noa_changed = true;
}
/* If at least two consecutive beacons were missed on the STA
* chanctx, stay on the STA channel for one extra beacon period,
* to resync the timer properly.
*/
if (ctx->active && sc->sched.beacon_miss >= 2)
sc->sched.offchannel_duration = 3 * beacon_int / 2;
if (sc->sched.offchannel_duration) {
noa_changed = true;
avp->offchannel_start = tsf_time;
avp->offchannel_duration =
sc->sched.offchannel_duration;
}
if (noa_changed)
avp->noa_index++;
break;
case ATH_CHANCTX_EVENT_BEACON_SENT:
if (!sc->sched.beacon_pending)
break;
sc->sched.beacon_pending = false;
if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON)
break;
sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_TIMER;
ath_chanctx_setup_timer(sc, sc->sched.switch_start_time);
break;
case ATH_CHANCTX_EVENT_TSF_TIMER:
if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_TIMER)
break;
if (!sc->cur_chan->switch_after_beacon &&
sc->sched.beacon_pending)
sc->sched.beacon_miss++;
sc->sched.state = ATH_CHANCTX_STATE_SWITCH;
ieee80211_queue_work(sc->hw, &sc->chanctx_work);
break;
case ATH_CHANCTX_EVENT_BEACON_RECEIVED:
if (!test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) ||
sc->cur_chan == &sc->offchannel.chan)
break;
ath_chanctx_adjust_tbtt_delta(sc);
sc->sched.beacon_pending = false;
sc->sched.beacon_miss = 0;
/* TSF time might have been updated by the incoming beacon,
* need update the channel switch timer to reflect the change.
*/
tsf_time = sc->sched.switch_start_time;
tsf_time -= (u32) sc->cur_chan->tsf_val +
ath9k_hw_get_tsf_offset(&sc->cur_chan->tsf_ts, NULL);
tsf_time += ath9k_hw_gettsf32(ah);
ath_chanctx_setup_timer(sc, tsf_time);
break;
case ATH_CHANCTX_EVENT_ASSOC:
if (sc->sched.state != ATH_CHANCTX_STATE_FORCE_ACTIVE ||
avp->chanctx != sc->cur_chan)
break;
sc->sched.state = ATH_CHANCTX_STATE_IDLE;
/* fall through */
case ATH_CHANCTX_EVENT_SWITCH:
if (!test_bit(ATH_OP_MULTI_CHANNEL, &common->op_flags) ||
sc->sched.state == ATH_CHANCTX_STATE_FORCE_ACTIVE ||
sc->cur_chan->switch_after_beacon ||
sc->cur_chan == &sc->offchannel.chan)
break;
/* If this is a station chanctx, stay active for a half
* beacon period (minus channel switch time)
*/
sc->next_chan = ath_chanctx_get_next(sc, sc->cur_chan);
cur_conf = &sc->cur_chan->beacon;
sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_TIMER;
tsf_time = TU_TO_USEC(cur_conf->beacon_interval) / 2;
if (sc->sched.beacon_miss >= 2) {
sc->sched.beacon_miss = 0;
tsf_time *= 3;
}
tsf_time -= sc->sched.channel_switch_time;
tsf_time += ath9k_hw_gettsf32(sc->sc_ah);
sc->sched.switch_start_time = tsf_time;
ath_chanctx_setup_timer(sc, tsf_time);
sc->sched.beacon_pending = true;
break;
case ATH_CHANCTX_EVENT_ENABLE_MULTICHANNEL:
if (sc->cur_chan == &sc->offchannel.chan ||
sc->cur_chan->switch_after_beacon)
break;
sc->next_chan = ath_chanctx_get_next(sc, sc->cur_chan);
ieee80211_queue_work(sc->hw, &sc->chanctx_work);
break;
case ATH_CHANCTX_EVENT_UNASSIGN:
if (sc->cur_chan->assigned) {
if (sc->next_chan && !sc->next_chan->assigned &&
sc->next_chan != &sc->offchannel.chan)
sc->sched.state = ATH_CHANCTX_STATE_IDLE;
break;
}
ctx = ath_chanctx_get_next(sc, sc->cur_chan);
sc->sched.state = ATH_CHANCTX_STATE_IDLE;
if (!ctx->assigned)
break;
sc->next_chan = ctx;
ieee80211_queue_work(sc->hw, &sc->chanctx_work);
break;
}
spin_unlock_bh(&sc->chan_lock);
}
